U.S. patent application number 15/784807 was filed with the patent office on 2018-02-08 for chip package having die structures of different heights and method of forming same.
The applicant listed for this patent is Taiwan Semiconductor Manufacturing Company, Ltd.. Invention is credited to Weiming Chris Chen, Shang-Yun Hou, Hsien-Pin Hu, Wen-Hsin Wei, Chi-Hsi Wu, Chen-Hua Yu.
Application Number | 20180040586 15/784807 |
Document ID | / |
Family ID | 57582470 |
Filed Date | 2018-02-08 |
United States Patent
Application |
20180040586 |
Kind Code |
A1 |
Wei; Wen-Hsin ; et
al. |
February 8, 2018 |
Chip Package Having Die Structures of Different Heights and Method
of Forming Same
Abstract
Structures and formation methods of a chip package are provided.
The chip package includes a chip stack including a number of
semiconductor dies. The chip package also includes a semiconductor
chip, and the semiconductor chip is higher than the chip stack. The
chip package further includes a package layer covering a top and
sidewalls of the chip stack and sidewalls of the semiconductor
chip.
Inventors: |
Wei; Wen-Hsin; (Hsinchu,
TW) ; Wu; Chi-Hsi; (Hsinchu, TW) ; Yu;
Chen-Hua; (Hsinchu, TW) ; Hu; Hsien-Pin;
(Zhubei City, TW) ; Hou; Shang-Yun; (Jubei City,
TW) ; Chen; Weiming Chris; (Taipei City, TW) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Taiwan Semiconductor Manufacturing Company, Ltd. |
Hsinchu |
|
TW |
|
|
Family ID: |
57582470 |
Appl. No.: |
15/784807 |
Filed: |
October 16, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
15003150 |
Jan 21, 2016 |
9806058 |
|
|
15784807 |
|
|
|
|
62188169 |
Jul 2, 2015 |
|
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01L 23/49816 20130101;
H01L 2924/182 20130101; H01L 25/18 20130101; H01L 2224/73259
20130101; H01L 2924/1436 20130101; H01L 2224/32145 20130101; H01L
2224/16235 20130101; H01L 2224/06181 20130101; H01L 21/568
20130101; H01L 21/486 20130101; H01L 2224/96 20130101; H01L
2924/1437 20130101; H01L 24/03 20130101; H01L 2224/13111 20130101;
H01L 25/50 20130101; H01L 2224/16146 20130101; H01L 2225/06513
20130101; H01L 2224/13082 20130101; H01L 2224/13147 20130101; H01L
25/0652 20130101; H01L 24/09 20130101; H01L 2224/04105 20130101;
H01L 2224/12105 20130101; H01L 2224/16238 20130101; H01L 2224/17181
20130101; H01L 2224/32225 20130101; H01L 23/5384 20130101; H01L
2225/06517 20130101; H01L 2924/15311 20130101; H01L 2924/18161
20130101; H01L 24/96 20130101; H01L 2224/81815 20130101; H01L
2224/08235 20130101; H01L 2224/16227 20130101; H01L 23/49827
20130101; H01L 24/13 20130101; H01L 24/17 20130101; H01L 2225/06541
20130101; H01L 24/81 20130101; H01L 2224/13139 20130101; H01L 24/16
20130101; H01L 2224/9202 20130101; H01L 23/49833 20130101; H01L
2224/73204 20130101; H01L 2224/0401 20130101; H01L 23/3128
20130101; H01L 2224/13111 20130101; H01L 2924/014 20130101; H01L
2224/96 20130101; H01L 2224/81 20130101; H01L 2224/96 20130101;
H01L 2224/03 20130101; H01L 2224/96 20130101; H01L 2224/11
20130101; H01L 2224/73204 20130101; H01L 2224/16225 20130101; H01L
2224/32225 20130101; H01L 2924/00 20130101; H01L 2224/73204
20130101; H01L 2224/16145 20130101; H01L 2224/32145 20130101; H01L
2924/00 20130101 |
International
Class: |
H01L 25/065 20060101
H01L025/065; H01L 25/18 20060101 H01L025/18; H01L 25/00 20060101
H01L025/00; H01L 23/00 20060101 H01L023/00 |
Claims
1. A package comprising: a substrate; a first chip stack bonded to
the substrate; a second chip stack bonded to the substrate adjacent
the first chip stack; and a molding compound layer extending along
a first side of the first chip stack, the first side of the first
chip stack being a farthest side of the first chip stack from the
substrate.
2. The package of claim 1, further comprising an underfill layer
interposed between the substrate and the molding compound
layer.
3. The package of claim 2, wherein a topmost surface of the
underfill layer is above a bottommost surface of the first chip
stack and a bottommost surface of the second chip stack.
4. The package of claim 1, further comprising first connectors
between the first chip stack and the substrate, the first
connectors electrically and mechanically coupling the first chip
stack to the substrate.
5. The package of claim 4, further comprising second connectors
between the second chip stack and the substrate, the second
connectors electrically and mechanically coupling the second chip
stack to the substrate.
6. A package comprising: a substrate; a first semiconductor chip
attached to the substrate; a second semiconductor chip attached to
the substrate, the first semiconductor chip and the second
semiconductor chip being attached to a same side of the substrate;
and a molding compound layer surrounding the first semiconductor
chip and the second semiconductor chip, the molding compound layer
covering a top surface of the first semiconductor chip.
7. The package of claim 6, wherein the molding compound layer
covers a top surface of the second semiconductor chip.
8. The package of claim 6, wherein the second semiconductor chip is
exposed through the molding compound layer.
9. The package of claim 6, wherein the second semiconductor chip
has a greater height than the first semiconductor chip.
10. The package of claim 6, further comprising an underfill layer
surrounding the first semiconductor chip and the second
semiconductor chip, an interface between the underfill layer and
the molding compound layer being above a bottommost surface of the
first semiconductor chip and a bottommost surface of the second
semiconductor chip.
11. The package of claim 10, wherein a first size of first fillers
dispersed in the molding compound layer is less than a second size
of second fillers dispersed in the underfill layer.
12. The package of claim 10, wherein a first density of first
fillers dispersed in the molding compound layer is less than a
second density of second fillers dispersed in the underfill
layer.
13. The package of claim 10, further comprising connectors between
the first semiconductor chip and the substrate, the connectors
being surrounded by the underfill layer.
14. A package comprising: a substrate; a semiconductor chip bonded
to the substrate; a first chip stack bonded to the substrate; an
underfill layer extending between the semiconductor chip and the
substrate and between the first chip stack and the substrate, at
least a portion of the underfill layer extending along sidewalls of
the semiconductor chip and along sidewalls of the first chip stack;
and a package layer over the underfill layer, the package layer
extending along a topmost surface of the first chip stack, an
interface between the underfill layer and package layer being above
a bottommost surface of the first chip stack and below the topmost
surface of the first chip stack.
15. The package of claim 14, wherein the first chip stack
comprises: a plurality of dies; and an encapsulant extending along
sidewalls of the plurality of dies and across the interface between
the underfill layer and package layer.
16. The package of claim 15, wherein the encapsulant extends along
and physically contacts a topmost surface of at least one die of
the plurality of dies.
17. The package of claim 14, wherein the package layer extends
along a topmost surface of the semiconductor chip.
18. The package of claim 14, wherein a topmost surface of the
semiconductor chip is substantially level with a topmost surface of
the package layer.
19. The package of claim 14, wherein a first size of first fillers
dispersed in the underfill layer is less than a second size of
second fillers dispersed in the package layer.
20. The package of claim 14, wherein a first density of first
fillers dispersed in the underfill layer is less than a second
density of second fillers dispersed in the package layer.
Description
PRIORITY CLAIM AND CROSS-REFERENCE
[0001] This application is a continuation of U.S. patent
application Ser. No. 15/003,150, filed on Jan. 21, 2016, entitled
"Chip Package Having Die Structures of Different Heights and Method
of Forming Same," which claims the benefit of U.S. Provisional
Application No. 62/188,169, filed on Jul. 2, 2015, entitled
"Structure and Formation Method of Package," which applications are
hereby incorporated herein by reference.
BACKGROUND
[0002] Semiconductor devices are used in a variety of electronic
applications, such as personal computers, cell phones, digital
cameras, and other electronic equipment. These semiconductor
devices are fabricated by sequentially depositing insulating or
dielectric layers, conductive layers, and semiconductor layers over
a semiconductor substrate, and patterning the various material
layers using lithography and etching processes to form circuit
components and elements on the semiconductor substrate.
[0003] The semiconductor industry continues to improve the
integration density of various electronic components (e.g.,
transistors, diodes, resistors, capacitors, etc.) by continual
reductions in minimum feature size, which allow more components to
be integrated into a given area. These smaller electronic
components also use a smaller package that utilizes less area or a
smaller height, in some applications.
[0004] New packaging technologies have been developed to improve
the density and functions of semiconductor devices. These
relatively new types of packaging technologies for semiconductor
devices face manufacturing challenges.
BRIEF DESCRIPTION OF THE DRAWINGS
[0005] Aspects of the present disclosure are best understood from
the following detailed description when read with the accompanying
figures. It should be noted that, in accordance with the standard
practice in the industry, various features are not drawn to scale.
In fact, the dimensions of the various features may be arbitrarily
increased or reduced for clarity of discussion.
[0006] FIGS. 1A-1F are cross-sectional views of various stages of a
process for forming a chip package, in accordance with some
embodiments.
[0007] FIG. 2 is a cross-sectional view of a chip package, in
accordance with some embodiments.
[0008] FIGS. 3A-3E are cross-sectional views of various stages of a
process for forming a chip package, in accordance with some
embodiments.
[0009] FIG. 4 is a cross-sectional view of a chip package, in
accordance with some embodiments.
[0010] FIG. 5 is a cross-sectional view of a chip package, in
accordance with some embodiments.
DETAILED DESCRIPTION
[0011] The following disclosure provides many different
embodiments, or examples, for implementing different features of
the provided subject matter. Specific examples of components and
arrangements are described below to simplify the present
disclosure. These are, of course, merely examples and are not
intended to be limiting. For example, the formation of a first
feature over or on a second feature in the description that follows
may include embodiments in which the first and second features are
formed in direct contact, and may also include embodiments in which
additional features may be formed between the first and second
features, such that the first and second features may not be in
direct contact. In addition, the present disclosure may repeat
reference numerals and/or letters in the various examples. This
repetition is for the purpose of simplicity and clarity and does
not in itself dictate a relationship between the various
embodiments and/or configurations discussed.
[0012] Further, spatially relative terms, such as "beneath,"
"below," "lower," "above," "upper" and the like, may be used herein
for ease of description to describe one element or feature's
relationship to another element(s) or feature(s) as illustrated in
the figures. The spatially relative terms are intended to encompass
different orientations of the device in use or operation in
addition to the orientation depicted in the figures. The apparatus
may be otherwise oriented (rotated 90 degrees or at other
orientations) and the spatially relative descriptors used herein
may likewise be interpreted accordingly.
[0013] Some embodiments of the disclosure are described. FIGS.
1A-1F are cross-sectional views of various stages of a process for
forming a chip package, in accordance with some embodiments.
Additional operations can be provided before, during, and/or after
the stages described in FIGS. 1A-1F. Some of the stages that are
described can be replaced or eliminated for different embodiments.
Additional features can be added to the semiconductor device
structure. Some of the features described below can be replaced or
eliminated for different embodiments. Although some embodiments are
discussed with operations performed in a particular order, these
operations may be performed in another logical order.
[0014] As shown in FIG. 1A, a semiconductor chip 10 and chip stacks
20 and 30 are bonded over a substrate 180, in accordance with some
embodiments. In some embodiments, the semiconductor chip 10 is
higher than the chip stack 20 or 30. In some embodiments, the
semiconductor chip 10 includes a semiconductor substrate 100 and an
interconnection structure (not shown) formed on the semiconductor
substrate 100. For example, the interconnection structure is formed
on a bottom surface of the semiconductor substrate 100. The
interconnection structure includes multiple interlayer dielectric
layers and multiple conductive features formed in the interlayer
dielectric layers. These conductive features include conductive
lines, conductive vias, and conductive contacts. Some portions of
the conductive features may be used as conductive pads.
[0015] In some embodiments, various device elements are formed in
the semiconductor substrate 100. Examples of the various device
elements include transistors (e.g., metal oxide semiconductor field
effect transistors (MOSFET), complementary metal oxide
semiconductor (CMOS) transistors, bipolar junction transistors
(BJT), high voltage transistors, high frequency transistors,
p-channel and/or n-channel field effect transistors (PFETs/NFETs),
etc.), diodes, or other suitable elements.
[0016] The device elements are interconnected through the
interconnection structure to form integrated circuit devices. The
integrated circuit devices include logic devices, memory devices
(e.g., static random access memories, SRAMs), radio frequency (RF)
devices, input/output (I/O) devices, system-on-chip (SoC) devices,
other applicable types of devices, or a combination thereof. In
some embodiments, the semiconductor chip 10 is a system-on-chip
(SoC) chip that includes multiple functions.
[0017] In some embodiments, each of the chip stacks 20 and 30
includes multiple semiconductor dies that are stacked. As shown in
FIG. 1A, the chip stack 20 includes semiconductor dies 200, 202A,
202B, 202C, 202D, 202E, 202F, 202G, and 202H. In some embodiments,
the chip stack 20 includes a molding compound layer 210 that
encapsulates and protects these semiconductor dies. The molding
compound layer 210 may include an epoxy-based resin with fillers
dispersed therein. The fillers may include insulating fibers,
insulating particles, other suitable elements, or a combination
thereof.
[0018] In some embodiments, the semiconductor dies 202A, 202B,
202C, 202D, 202E, 202F, 202G, and 202H are memory dies. The memory
dies may include memory devices such as static random access memory
(SRAM) devices, dynamic random access memory (DRAM) devices, other
suitable devices, or a combination thereof. In some embodiments,
the semiconductor die 200 is a control die that is electrically
connected to the memory dies stacked thereon. The chip stack 20 may
function as a high bandwidth memory (HBM). In some embodiments, the
chip stack 30 is also a high bandwidth memory that includes
multiple stacked memory dies.
[0019] Many variations and/or modifications can be made to
embodiments of the disclosure. In some embodiments, one of the chip
stacks 20 and 30 includes only a single chip. In these cases, the
reference number 20 or 30 can be used to designate a semiconductor
chip.
[0020] In some embodiments, conductive bonding structures 206 are
formed between these semiconductor dies 200, 202A, 202B, 202C,
202D, 202E, 202F, 202G, and 202H to bond them together, as shown in
FIG. 1A. In some embodiments, each of the conductive bonding
structures 206 includes metal pillars and/or solder bumps. In some
embodiments, underfill elements 208 are formed between these
semiconductor dies to surround and protect the conductive bonding
structures 206. In some embodiments, the underfill element 208
includes an epoxy-based resin with fillers dispersed therein. The
fillers may include insulating fibers, insulating particles, other
suitable elements, or a combination thereof. In some embodiments,
the size and/or density of the fillers dispersed in the underfill
element 208 is smaller than those dispersed in the molding compound
layer 210.
[0021] In some embodiments, multiple conductive features 282 are
formed in some of the semiconductor dies in the chip stack 20, as
shown in FIG. 1A. Each of the conductive features 282 penetrates
through one of the semiconductor dies 200, 202A, 202B, 202C, 202D,
202E, 202F, 202G, and 202H and is electrically connected to one of
the conductive bonding structures 206. The conductive features 282
are used as through substrate vias (TSVs). Electrical signals can
be transmitted between these vertically stacked semiconductor dies
through the conductive features 282.
[0022] As shown in FIG. 1A, the semiconductor chip 10 and the chip
stacks 20 and 30 are bonded onto the substrate 180 through
conductive bonding structures 106, in accordance with some
embodiments. In some embodiments, the conductive bonding structures
106 include solder bumps, metal pillar bumps, other suitable
structures, or a combination thereof. In some embodiments, each of
the conductive bonding structures 106 includes a metal pillar bump
102, a solder element 104, and a metal pillar bump 184, as shown in
FIG. 1A. For example, the metal pillar bumps 102 and 184 are
substantially made of copper.
[0023] In some embodiments, a number of metal pillar bumps 102 are
formed over the bottom surfaces of the semiconductor chip 10 and
the chip stacks 20 and 30. In some embodiments, a number of metal
pillar bumps 184 are formed over the substrate 180 before the
bonding with the semiconductor chip 10 and the chip stacks 20 and
30.
[0024] In some embodiments, solder material, such as solder paste,
is applied on one or both of the metal pillar bumps 102 and 184
before the bonding process. Afterwards, the metal pillar bumps 102
and 184 are bonded together through the solder material. The solder
material forms the solder elements 104 between the metal pillar
bumps 102 and 184. As a result, the conductive bonding structures
106 are formed, as shown in FIG. 1A. In some embodiments, the
solder material is an alloy material that includes tin (Sn). The
solder material also includes another element. The element may
include lead, silver, copper, nickel, bismuth, another suitable
element, or a combination thereof. In some embodiments, the solder
material does not include lead.
[0025] In some embodiments, the substrate 180 includes a
semiconductor material, a ceramic material, an insulating material,
a polymer material, another suitable material, or a combination
thereof. In some embodiments, the substrate 180 is a semiconductor
substrate. The semiconductor substrate may be a semiconductor
wafer, such as a silicon wafer.
[0026] As shown in FIG. 1A, a number of conductive features 182 are
formed in the substrate 180, in accordance with some embodiments.
In some embodiments, the conductive features 182 are formed before
the formation of the metal pillar bumps 184. In some embodiments,
each of the conductive features 182 is electrically connected to
one of the metal pillar bumps 184. Interconnection structures (not
shown) including, for example, redistribution layers may be used to
form electrical connections between the conductive features 182 and
the metal pillar bumps 184. In some embodiments, insulating
elements (not shown) are formed between the conductive features 182
and the substrate 180 to prevent short circuiting between different
conductive features 182.
[0027] In some embodiments, the conductive features 182 are made of
copper, aluminum, titanium, tungsten, cobalt, gold, platinum,
another suitable material, or a combination thereof. In some
embodiments, the insulating elements are made of silicon oxide,
silicon nitride, silicon oxynitride, silicon carbide, another
suitable material, or a combination thereof. In some embodiments,
one or more photolithography and etching processes are used to form
a number of openings that define the positions of the conductive
features 182. Afterwards, an insulating layer and a conductive
layer are sequentially deposited over the substrate 180 to fill the
openings. A planarization process is then performed to remove the
portions of the insulating layer and the conductive layer outside
of the openings. As a result, the remaining portions of the
insulating layer and the conductive layer in the openings form the
insulating elements and the conductive features 182,
respectively.
[0028] As shown in FIG. 1B, an underfill layer 108 is formed to
surround and protect the conductive bonding structures 106, in
accordance with some embodiments. In some embodiments, the
underfill layer 108 is in direct contact with the conductive
bonding structures 106. In some embodiments, a liquid underfill
material is dispensed by capillary action and cured to form the
underfill layer 108. In some embodiments, the underfill layer 108
includes an epoxy-based resin with fillers dispersed therein. The
fillers may include fibers, particles, other suitable elements, or
a combination thereof.
[0029] As shown in FIG. 1C, a package layer 110 is formed over the
substrate 180 to encapsulate the semiconductor chip 10 and the chip
stacks 20 and 30, in accordance with some embodiments. In some
embodiments, the package layer 110 fills gaps between the
semiconductor chip 10 and the chip stack 20 or 30. In some
embodiments, the package layer 110 is in direct contact with the
underfill layer 108. In some embodiments, the package layer 110 is
not in direct contact with the conductive bonding structures 106.
In some embodiments, the package layer 110 is in direct contact
with the molding compound layers 210 of the chip stacks 20 and
30.
[0030] In some embodiments, the package layer 110 includes a
polymer material. In some embodiments, the package layer 110 is a
molding compound layer. The molding compound layer may include an
epoxy-based resin with fillers dispersed therein. The fillers may
include insulating fibers, insulating particles, other suitable
elements, or a combination thereof. In some embodiments, the size
and/or density of the fillers dispersed in the package layer 110 is
greater than those dispersed in the underfill layer 108.
[0031] In some embodiments, a liquid molding compound material is
applied, and a thermal operation is then applied to cure the liquid
molding compound material. As a result, the liquid molding compound
material is hardened and transformed into the package layer 110. In
some embodiments, the thermal operation is performed at a
temperature in a range from about 200 degrees C. to about 230
degrees C. The operation time of the thermal operation may be in a
range from about 1 hour to about 3 hours.
[0032] As shown in FIG. 1D, the package layer 110 is planarized
such that the top surface of the semiconductor chip 10 is exposed,
in accordance with some embodiments. In some embodiments, the top
surfaces of the semiconductor chip 10 and the package layer 110 are
substantially coplanar with each other. In some embodiments, the
package layer 110 is planarized using a grinding process, a
chemical mechanical polishing (CMP) process, another applicable
process, or a combination thereof. In some embodiments, the top
surface of the chip stack 20 or 30 remains covered by the package
layer 110. In some embodiments, the chip stacks 20 and 30 are
protected by the package layer 110 during the planarization
process. The chip stacks 20 and 30 are not ground during the
planarization process. Therefore, the chip stacks 20 and 30 are
prevented from being damaged during the planarization process. The
quality and reliability of the chip stacks 20 and 30 are
significantly improved.
[0033] In some embodiments, the package layer 110 covers the top
and the sidewalls of the chip stacks 20 and 30, as shown in FIG.
1D. In some embodiments, the top surface of the semiconductor chip
10 is not covered by the package layer 110. In some embodiments,
the top surface of the package layer 110 is substantially coplanar
with the top surface of the semiconductor chip 10, which may
facilitate subsequent processes.
[0034] As shown in FIG. 1E, the substrate 180 is thinned to expose
the conductive features 182, in accordance with some embodiments.
In some embodiments, each of the conductive features 182 penetrates
through the substrate 180. In some embodiments, each of the
conductive features 182 is electrically connected to one of the
conductive bonding structures 106. In some embodiments, the
structure shown in FIG. 1D is turned upside down. Afterwards, the
substrate 180 is thinned using a planarization process to expose
the conductive features 182. The planarization process may include
a CMP process, a grinding process, an etching process, another
applicable process, or a combination thereof.
[0035] Afterwards, conductive elements are formed over the
substrate 180, as shown in FIG. 1E in accordance with some
embodiments. In some embodiments, the conductive elements include
metal pillars 114 and solder elements 116, as shown in FIG. 1E.
However, many variations and/or modifications can be made to
embodiments of the disclosure. In some other embodiments, the
conductive elements have different structures. For example, the
conductive elements do not include metal pillars. The conductive
elements may only include solder bumps. In some embodiments, a
buffer layer 112 is formed to protect the conductive elements. In
some embodiments, each of the metal pillars 114 is electrically
connected to one of the conductive features 182. In some
embodiments, the buffer layer 112 extends along portions of the
sidewalls of the metal pillars 114, as shown in FIG. 1E. In some
embodiments, the buffer layer 112 is made of silicon nitride,
silicon oxynitride, silicon oxide, polyimide, epoxy resin,
polybenzoxazole (PBO), another suitable material, or a combination
thereof.
[0036] As shown in FIG. 1F, the structure shown in FIG. 1E is
bonded onto a substrate 118, in accordance with some embodiments.
In some embodiments, the substrate 118 is a circuit board such as a
printed circuit board. In some other embodiments, the substrate 118
is a ceramic substrate. In some embodiments, conductive elements
120 and 124 are formed on opposite surfaces of the substrate 118,
as shown in FIG. 1F. In some embodiments, the conductive elements
120 and 124 are solder bumps such as controlled collapse chip
connection (C4) bumps and/or ball grid array (BGA) bumps. In some
embodiments, the conductive elements 120 and the solder elements
116 are reflowed and bonded together, as shown in FIG. 1F.
[0037] In some embodiments, each of the conductive elements 120 is
electrically connected to one of the conductive elements 124
through conductive features (not shown) formed in the substrate
118. The conductive features may include conductive lines and
conductive vias. In some embodiments, an underfill layer 122 is
then formed between the substrate 118 and the substrate 180 to
protect the conductive bonding structures therebetween.
[0038] Many variations and/or modifications can be made to
embodiments of the disclosure. FIG. 2 is a cross-sectional view of
a chip package, in accordance with some embodiments. In some
embodiments, the underfill layer 108 is not formed. In some
embodiments, the package layer 110 fills the space between the
substrate 180 and the semiconductor chips including the
semiconductor chip 10 and the chip stacks 20 and 30. The package
layer 110 surrounds the conductive bonding structures 106. In some
embodiments, since the underfill layer 108 is not formed, the
package layer 110 is in direct contact with the conductive bonding
structures 106.
[0039] In some embodiments, the substrate 180 is used as an
interposer. In some embodiments, the interposer does not include
active devices therein. In some other embodiments, the interposer
includes one or more active devices formed therein. In some
embodiments, the substrate 180 is a silicon interposer. The
substrate 180 may be used to improve the structural strength and
reliability of the chip package. However, embodiments of the
disclosure are not limited thereto. Many variations and/or
modifications can be made to embodiments of the disclosure. In some
embodiments, the substrate 180 is not formed.
[0040] FIGS. 3A-3E are cross-sectional views of various stages of a
process for forming a chip package, in accordance with some
embodiments. As shown in FIG. 3A, the semiconductor chip 10 and the
chip stacks 20 and 30 are attached on a carrier substrate 300, in
accordance with some embodiments. An adhesion layer (not shown) may
be used to attach the semiconductor chip 10 and the chip stacks 20
and 30 onto the carrier substrate 300. In some embodiments, the
carrier substrate 300 includes a glass substrate, a ceramic
substrate, a semiconductor substrate, a polymer substrate, another
suitable substrate, or a combination thereof. In some embodiments,
the carrier substrate 300 is a temporary substrate to support the
semiconductor chip 10 and the chip stacks 20 and 30 during
subsequent processes. Afterwards, the carrier substrate 300 may be
removed.
[0041] As shown in FIG. 3B, a package layer 310 is formed over the
carrier substrate 300 to encapsulate the semiconductor chip 10 and
the chip stacks 20 and 30, in accordance with some embodiments. In
some embodiments, the package layer 310 fills gaps between the
semiconductor chip 10 and the chip stack 20 or 30. In some
embodiments, the package layer 310 is in direct contact with the
molding compound layers 210 of the chip stacks 20 and 30.
[0042] In some embodiments, the package layer 310 includes a
polymer material. In some embodiments, the package layer 310 is a
molding compound layer. The molding compound layer may include an
epoxy-based resin with fillers dispersed therein. The fillers may
include insulating fibers, insulating particles, other suitable
elements, or a combination thereof.
[0043] In some embodiments, a liquid molding compound material is
applied, and a thermal operation is then applied to cure the liquid
molding compound material. As a result, the liquid molding compound
material is hardened and transformed into the package layer 310. In
some embodiments, the thermal operation is performed at a
temperature in a range from about 200 degrees C. to about 230
degrees C. The operation time of the thermal operation may be in a
range from about 1 hour to about 3 hours.
[0044] As shown in FIG. 3C, the package layer 310 is planarized so
that the top surface of the semiconductor chip 10 is exposed, in
accordance with some embodiments. In some embodiments, the package
layer 310 is planarized using a grinding process, a chemical
mechanical polishing (CMP) process, another applicable process, or
a combination thereof. In some embodiments, the top surface of the
chip stack 20 or 30 remains covered by the package layer 310. In
some embodiments, the chip stacks 20 and 30 are protected by the
package layer 310 during the planarization process. The chip stacks
20 and 30 are not ground during the planarization process.
Therefore, the chip stacks 20 and 30 are prevented from being
damaged during the planarization process. The quality and
reliability of the chip stacks 20 and 30 are significantly
improved.
[0045] In some embodiments, the package layer 310 covers the top
and the sidewalls of the chip stacks 20 and 30, as shown in FIG.
3C. In some embodiments, the top surface of the semiconductor chip
10 is not covered by the package layer 310. In some embodiments,
the top surface of the package layer 310 is substantially coplanar
with the top surface of the semiconductor chip 10, which may
facilitate subsequent processes.
[0046] As shown in FIG. 3D, the carrier substrate 300 is removed
such that the bottom surfaces of the semiconductor chip 10, the
chip stacks 20 and 30, and the package layer 310 are exposed, in
accordance with some embodiments. In some embodiments, the bottom
surfaces of the semiconductor chip 10, the chip stacks 20 and 30,
and the package layer 310 are substantially coplanar with each
other.
[0047] Afterwards, conductive elements are formed over the bottom
surfaces of the semiconductor chip 10 and the chip stacks 20 and
30, as shown in FIG. 3D in accordance with some embodiments. In
some embodiments, the conductive elements include metal pillars 314
and solder elements 316, as shown in FIG. 1E. In some other
embodiments, the conductive elements include other configurations.
In some embodiments, a buffer layer (not shown) is formed to
protect the conductive elements.
[0048] As shown in FIG. 3E, the structure shown in FIG. 3D is
bonded onto a substrate 318, in accordance with some embodiments.
In some embodiments, the substrate 318 is a circuit board such as a
printed circuit board. In some other embodiments, the substrate 318
is a ceramic substrate. In some embodiments, conductive elements
320 and 324 are formed on opposite surfaces of the substrate 318,
as shown in FIG. 3E. In some embodiments, the conductive elements
320 and 324 are solder bumps such as controlled collapse chip
connection (C4) bumps and/or ball grid array (BGA) bumps. In some
embodiments, the conductive elements 320 and the solder elements
316 are reflowed and bonded together, as shown in FIG. 3E.
[0049] In some embodiments, each of the conductive elements 320 is
electrically connected to one of the conductive elements 324
through conductive features (not shown) formed in the substrate
318. The conductive features may include conductive lines and
conductive vias. In some embodiments, an underfill layer 322 is
then formed between the substrate 318 and the chips including the
semiconductor chip 10 and the chip stacks 20 and 30 to protect the
conductive bonding structures therebetween. In some embodiments,
the package layer 310 is not in direct contact with the conductive
bonding structures therebetween.
[0050] In some embodiments, due to the protection of the package
layer 310, the chip stacks 20 and 30 are prevented from being
damaged during the fabrication processes. For example, the stress
generated from the planarization of the package layer 310 and the
bonding process to the substrate 318 is buffered. The quality of
the chip package is improved.
[0051] Many variations and/or modifications can be made to
embodiments of the disclosure. FIG. 4 is a cross-sectional view of
a chip package, in accordance with some embodiments. In some
embodiments, the underfill layer 108 not only surrounds the
conductive bonding structures 106 but further extends on sidewalls
of the semiconductor chip 10. Portions of the sidewalls of the
semiconductor chip 10 are covered by the underfill layer 108. In
some embodiments, the underfill layer 108 extends on the chip
stacks 20 and 30. Portions of the sidewalls of the chip stacks 20
and 30 are covered by the underfill layer 108.
[0052] Many variations and/or modifications can be made to
embodiments of the disclosure. FIG. 5 is a cross-sectional view of
a chip package, in accordance with some embodiments. The structure
shown in FIG. 5 is similar to that shown in FIG. 1F. In some
embodiments, the semiconductor chip 10 is positioned between the
chip stack 20 and a semiconductor chip 40. In some embodiments, the
semiconductor chip 10 is higher than the chip stack 20 or the
semiconductor chip 40. In some embodiments, the heights of the
semiconductor chip 40 and the chip stack 20 are different from each
other. In some embodiments, the semiconductor chip 40 is higher
than the chip stack 20.
[0053] In some embodiments, the semiconductor chip 40 includes a
semiconductor substrate 400 and an interconnection structure (not
shown) formed on the semiconductor substrate 400. For example, the
interconnection structure is formed on a bottom surface of the
semiconductor substrate 400. The interconnection structure includes
multiple interlayer dielectric layers and multiple conductive
features formed in the interlayer dielectric layers. These
conductive features include conductive lines, conductive vias, and
conductive contacts. Some portions of the conductive features may
be used as conductive pads.
[0054] In some embodiments, similar to the semiconductor substrate
100, various device elements are formed in the semiconductor
substrate 400. Examples of the various device elements include
transistors (e.g., metal oxide semiconductor field effect
transistors (MOSFET), complementary metal oxide semiconductor
(CMOS) transistors, bipolar junction transistors (BJT), high
voltage transistors, high frequency transistors, p-channel and/or
n-channel field effect transistors (PFETs/NFETs), etc.), diodes, or
other suitable elements.
[0055] The device elements are interconnected through the
interconnection structure to form integrated circuit devices. The
integrated circuit devices include logic devices, memory devices
(e.g., static random access memories, SRAMs), radio frequency (RF)
devices, input/output (I/O) devices, system-on-chip (SoC) devices,
other applicable types of devices, or a combination thereof. In
some embodiments, the semiconductor chip 40 is a system-on-chip
(SoC) chip that includes multiple functions. In some embodiments,
one or more of the functions of the semiconductor chips 10 and 40
are different from each other.
[0056] Embodiments of the disclosure form a chip package including
a first semiconductor chip and a second semiconductor chip that may
be a chip stack. The heights of the first semiconductor chip and
the second semiconductor chip are different. A package layer, such
as a molding compound layer, is formed to encapsulate the first
semiconductor chip and the second semiconductor chip. The package
layer is thinned to expose the first semiconductor chip. During the
thinning process, the second semiconductor chip is protected by the
package layer without being directly ground. The second
semiconductor chip (or chip stack) is prevented from negatively
affected due to the protection of the package layer during the
thinning process. The performance and reliability of the chip
package are significantly improved.
[0057] In accordance with some embodiments, a chip package is
provided. The chip package includes a chip stack including a number
of semiconductor dies. The chip package also includes a
semiconductor chip, and the semiconductor chip is higher than the
chip stack. The chip package further includes a package layer
covering a top and sidewalls of the chip stack and sidewalls of the
semiconductor chip.
[0058] In accordance with some embodiments, a chip package is
provided. The chip package includes a first semiconductor chip and
a second semiconductor chip. The chip package also includes a
molding compound layer surrounding the first semiconductor chip and
the second semiconductor chip. The molding compound layer covers a
top surface of the first semiconductor chip, and a top surface of
the molding compound layer is substantially coplanar with a top
surface of the second semiconductor chip.
[0059] In accordance with some embodiments, a method for forming a
chip package is provided. The method includes bonding a first
semiconductor chip and a second semiconductor chip over a
substrate. The method also includes forming a package layer over
the substrate to encapsulate the first semiconductor chip and the
second semiconductor chip. The method further includes planarizing
the package layer so that a top surface of the second semiconductor
chip is exposed, and a top surface of the first semiconductor chip
is covered by the package layer.
[0060] In accordance with some embodiments, a package is provided.
The package includes a substrate, and a first chip stack bonded to
the substrate. The package also includes a second chip stack bonded
to the substrate adjacent the first chip stack. The package further
includes a molding compound layer extending along a first side of
the first chip stack, the first side of the first chip stack being
a farthest side of the first chip stack from the substrate.
[0061] In accordance with some embodiments, a package is provided.
The package includes a substrate, and a first semiconductor chip
attached to the substrate. The package also includes a second
semiconductor chip attached to the substrate, the first
semiconductor chip and the second semiconductor chip being attached
to a same side of the substrate. The package further includes a
molding compound layer surrounding the first semiconductor chip and
the second semiconductor chip, the molding compound layer covering
a top surface of the first semiconductor chip.
[0062] In accordance with some embodiments, a package is provided.
The package includes a substrate, a semiconductor chip bonded to
the substrate, and a first chip stack bonded to the substrate. The
package also includes an underfill layer extending between the
semiconductor chip and the substrate and between the first chip
stack and the substrate, at least a portion of the underfill layer
extending along sidewalls of the semiconductor chip and along
sidewalls of the first chip stack. The package further includes a
package layer over the underfill layer, the package layer extending
along a topmost surface of the first chip stack, an interface
between the underfill layer and package layer being above a
bottommost surface of the first chip stack and below the topmost
surface of the first chip stack.
[0063] The foregoing outlines features of several embodiments so
that those skilled in the art may better understand the aspects of
the present disclosure. Those skilled in the art should appreciate
that they may readily use the present disclosure as a basis for
designing or modifying other processes and structures for carrying
out the same purposes and/or achieving the same advantages of the
embodiments introduced herein. Those skilled in the art should also
realize that such equivalent constructions do not depart from the
spirit and scope of the present disclosure, and that they may make
various changes, substitutions, and alterations herein without
departing from the spirit and scope of the present disclosure.
* * * * *